Passive Q switching of the CO2 laser by a new class of saturable absorbers is reported. Results are presented for eight representatives of this class: benzene, chlorobenzene, bromobenzene, m‐dichlorobenzene o ‐dichlorobenzene, m ‐difluorobenzene, pentafluorobenzene, and hexafluorobenzene. These Q‐switching agents operate on a large number of lines in both the 9.6‐ and 10.6‐μ bands. Other aromatic halogens selected on the basis of their absorption spectra are expected to display similar Q‐switch characteristics. This new class of saturable absorbers provides increased flexibility in the production of CO2 laser pulses.